The utility of thiophosphorus compounds is well known in the field of insecticides and acaricides. This invention relates to a novel class of such compounds and to their use as insecticides when used in an insecticidally effective amount. More specifically, this invention relates to isourea acetylphosphate compounds having the formula ##STR1## wherein R is lower alkoxy, R.sub.1 is lower alkyl or lower alkoxy, R.sub.2 is allyl or lower alkyl, and R.sub.3 is selected from the group consisting of allyl, lower alkyl, phenyl, benzyl, and 3-methylphenyl; or R.sub.2 and R.sub.3 taken together are --CH.sub.2 (CH.sub.2).sub.3 CH.sub.2 -- or --CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 --.
By "lower alkyl" is meant straight- or branched-chain alkyl groups containing from 1 to 4 carbon atoms, inclusive. By "lower alkoxy" is meant straight- or branched-chain alkoxy groups having from 1 to 4 carbon atoms, inclusive.
By "insecticidally effective amount" is meant the amount of the herein disclosed insecticidal compounds which when applied to the habitat of insects in any conventional manner will kill or substantially injure a significant portion of the population thereon.